German Chancellor Angela Merkel said on Monday that she was in favor of acquiring the information on citizens who had allegedly sheltered millions in secret Swiss bank accounts.
"Like every reasonable person, I support doing everything we can to clamp down on tax evasion," Merkel told reporters. "If this data is relevant we should aim to get hold of it."
German media reported over the weekend that an informant had offered data of up to 1,500 possible tax evaders with accounts in Switzerland which could lead to 100 million euros for state coffers.
The Frankfurter Allgemeine Zeitung reported that the whistleblower is asking for 2.5 million euros for the confidential data.
German newspaper Financial Times Deutschland reported that the data belonged to German clients of HSBC. The paper said the data had come from a computer specialist at an HSBC bank in Geneva.
Politicians divided over buying stolen data
The case could spark a fight about banking secrecy between Germany and Switzerland. Top Swiss politicians, including President Doris Leuthard, and bankers warned Germany against acquiring the data.
In 2008, the German government paid an informant as much as five million euros for a CD containing a list with the names of German tax evaders with bank accounts in the Alpine principality of Liechtenstein.
The latest case has prompted heated debate in Germany about the legality and morality of buying a CD with information obtained illegally.
A senior ally of Chancellor Angela Merkel, Defense Minister Karl-Theodor zu Guttenberg, said the government would need to check the legal validity of the data.
"I have a problem with handing over money for something that has come into someone's possession in a legally questionable fashion," Guttenberg told Swiss daily Neue Zuercher Zeitung.
Questions of legality
The moral questions raised have prompted a debate across the political spectrum, with Switzerland warning that buying the CD would be illegal.
"Generally speaking we believe that it is difficult for states to use illegal data," said Swiss President Doris Leuthard. "This would mean doing business with criminals, which is against the law."
Members of opposition parties in Germany have encouraged the government to buy the data on behalf of "honest taxpayers." Some politicians from Chancellor Merkel's Christian Democratic Union have also called for the purchase of the CD to be considered.
Hot topic in the press
Officials in Berlin confirmed the reports on Saturday after the Frankfurter Allgemeine Zeitung and Sueddeutsche Zeitung first reported on the offer.
The informant reportedly handed over information on five individuals to prove the data's validity.
Both newspapers reported the data was offered to tax officials in the western state of North Rhine-Westphalia.
Editor: Sonia Phalnikar